1. Field of the Invention
The present invention relates to water purification systems and, more particularly, to apparatus for sealingly retaining a cartridge filter in place in a water purification unit.
2. Description of Related Art
For decades various water filtering and purifying devices have been used by consumers. Some of these devices perform primarily only a particulate filtering function to remove particulate matter. Some of these systems incorporate activated charcoal as a filtering medium to remove chlorine from the water obtained from municipal water sources. Some devices incorporate a source of ultraviolet light to help kill living microorganisms. To enhance such killing and to oxidize various compounds in the water, ozone may be injected into and mixed with the water.
While activated charcoal cartridge filters can be very effective in removing particulate matter and chlorine from water, they suffer major drawbacks. The contaminants or sludge filtered from the water will collect upon the filter. The sludge, particularly when it contains organic matter, serves as a breeding ground for bacteria, viruses and other microorganisms. These microorganisms often are conveyed downstream from the filter and are ultimately ingested by the consumer. Due to aging the normally compressible annular cartridge filter seating elements or annular support members may lose their sealing capability and permit bypass of water to be filtered. These potential health hazards can be avoided to some extent by regular replacement of the cartridge filter. Unfortunately, such replacement is often neglected by a consumer and the resulting health hazards may be life threatening. To avoid and eliminate such health hazards, the use of consumer oriented water filtering devices having mechanical filters for removing particulate matter has been banned in various communities around the world.